1. Field of the Invention
The invention relates to a method and module for controlling rotation of a motorized spindle.
2. Description of the Related Art
Vibration of high-speed spindles is considered a main cause of damage to such spindles.
Referring to FIG. 1, a conventional driving device 1 for a motorized spindle 2 is shown to include a detecting unit 11, and a driving unit 12 for driving the spindle 2. The detecting unit 11 generates a detecting signal upon detecting that vibration of the spindle 2 is greater than a predetermined vibration level, and outputs the detecting signal to the driving unit 12. The driving unit 12 stops driving the spindle 2 or reduces a rotation speed of the spindle 2 in accordance with the detecting signal from the detecting unit 11.
In such a driving device 1, it is important to appropriately decide the predetermined vibration level of the spindle 2. For example, if the predetermined vibration level of the spindle 2 is relatively high, the spindle 2 has been subjected to damaging vibration levels for a long period before the detecting unit 11 outputs the detecting signal to the driving unit 12, thereby reducing the service life of the spindle 2. On the other hand, if the predetermined vibration level of the spindle 2 is relatively low, the driving unit 12 reduces the rotation speed of the spindle 2 or stops driving the spindle 2, frequently, thereby adversely affecting transmission efficiency of the spindle 2.